Various embodiments of consumer-operated coin counting kiosks are disclosed in, for example: U.S. Pat. Nos. 5,620,079, 6,494,776, 7,520,374, 7,584,869, 7,653,599, 7,748,619, 7,815,071, and 7,865,432; and U.S. patent application Ser. Nos. 12/758,677, 12/806,531, 61/364,360, 61/409,050, and Ser. No. 13/489,043; each of which is incorporated herein in its entirety by reference.
Many consumer-operated kiosks, vending machines, and other commercial sales/service/rental machines discriminate between different coin denominations based on the size, weight and/or electromagnetic properties of metal alloys in the coin. With some known technologies, a coin can be routed through an oscillating electromagnetic field that interacts with the coin. As the coin passes through the electromagnetic field, coin properties are sensed, such as changes in inductance (from which the diameter of the coin can be derived) or the quality factor related to the amount of energy dissipated (from which conductivity/metallurgy of the coin can be obtained). The results of the interaction can be collected and compared against a list of sizes and electromagnetic properties of known coins to determine the denomination of the coin. In other known technologies, a coin can be rolled along a predetermined path and the velocity of the coin or the time to reach a certain point along the path can be measured. By comparing the measured time or velocity against the corresponding values for known coins, the denomination of the coin can be determined.
However, many coins may have similar size, mass, metallurgy, and/or spectral properties. This is especially the case in markets which are proximate to multiple countries having different coin denominations. As a result, coin counting mistakes may occur due to the coin similarities, resulting in possible losses for consumer coin counting kiosk operators. Accordingly, it would be advantageous to provide robust coin discrimination systems and methods that would work reliably for coins having similar size, mass, metallurgy, and/or spectral properties.